In a mobile communication system, a communication terminal such as a mobile telephone connects to a base station and thereby can access the Internet via a core network. The communication terminal performs communication over a communication path (e.g., a bearer) established with an apparatus (e.g., a gateway) provided in the core network.
In order to construct the bearer, the base station and the gateway construct a tunnel by encapsulating a packet. In order to construct the tunnel, the base station and the gateway add QoS (Quality of Service) information to the packet. Communication apparatuses in the mobile communication system can perform packet forwarding control (e.g., communication quality control), based on the QoS information added to the packet.
NPL 1 discloses a technique related to QoS control in a mobile communication system. In NPL 1, table 6.1.7 discloses a correspondence between a communication service and a QCI (QoS Class Identifier). For example, when constructing a GTP (GPRS Tunneling Protocol) tunnel corresponding to a bearer, a gateway apparatus and a base station add QoS information (e.g., DSCP (Differentiated Service Code Point)) associated with the QCI of the bearer to a packet. The gateway apparatus and the base station add QoS information to a packet, thereby performing communication quality control on the packet.